A centrifugal heat engine operating on the Rankine cycle and employing a rotatable boiler is disclosed in U.S. Pat. No. 3,590,786 wherein liquid working fluid in the boiler is held against a cylindrical, transverse heat transfer surface by centrifugal force created by rotation of the boiler. Power is generated using a separate stationary turbine and condenser utilizing vaporized working fluid produced by the boiler. As stated in this patent, rotatable boilers are advantageous because a sharp interface between liquid and vapor in the boiler is established by the centrifugal force acting on the liquid, the force effecting a heat flux much greater than can be achieved under normal gravity conditions. U.S. Pat. No. 3,613,368 discloses a Rankine cycle heat engine having a rotatable boiler and having a rotatable turbine and condenser as well.
Devices disclosed in these patents are advantageous because of their ability to utilize external combustion, and because of the large power output to physical size and weight achieved by such devices. It is therefore an object of the present invention to provide a new and improved centrifugal heat engine in order to further improve the power-to-size ratio of a centrifugal heat engine.